Hello Jason- The suggested approximate cook time is 60-90 minutes, as it appears in the text of the recipe. Note however that this is only an approximation. The amount of time that it takes for a tender cut (in this case- Beef Tenderloin) to cook is determined by the thermal conductivity of the specific protein. This varies from pork to beef to fish etc. Another determining factor is the shape of the protein. Is it a cylinder, cube, slab, etc. Lastly, another factor at play (and the most important of them all) is the thickness of the piece of food to be cooked. Try having a look at our iOS app, The PolyScience Sous Vide Toolbox, for further clarification or the cooking time charts as printed in Modernist Cuisine, Modernist Cuisine at Home, and Immersed. In short- giving specific cook times for the cooking of proteins, especially those with great thickness, is tricky because it really depends on and differs from steak to steak.

When discussing cooking temperatures for tender cuts of protein, the choice really comes down to the degree of doneness that you prefer. Do you like you steak cooked rare? Medium well? Well done? The choice is really up to you.